CN108794310B - Method for separating and purifying two acetals and raw material alcohol by pressure swing distillation - Google Patents
Method for separating and purifying two acetals and raw material alcohol by pressure swing distillation Download PDFInfo
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Abstract
The invention discloses a method for separating and purifying two acetals and a raw material alcohol by pressure swing distillation, which takes two crude products of methoxy-methoxybutane and n-butyl alcohol and methoxy-methoxyisobutane and isobutanol as separation materials, wherein the proportions of the two compounds in the two crude products are respectively 1 percent to 99 percent to 1 percent; the invention relates to the technical field of chemical separation, in particular to a method for separating and purifying two acetals and raw material alcohol by pressure swing distillation, which introduces a distillation separation process of pressure swing distillation combined operation, realizes clean and efficient separation by utilizing the property that different azeotropic ratios exist between methoxy methoxybutane and n-butyl alcohol and between methoxy methoxyisobutane and isobutanol under different pressures, skillfully designs the re-circulation separation of materials which are not separated and azeotropy formed, finally realizes the purpose of efficient separation, does not use a third compound in the process, avoids secondary pollution caused by introducing other compounds, increases the separation difficulty and load, has strong practicability and is easy to popularize and use.
Description
Technical Field
The invention belongs to the technical field of chemical separation, and relates to a preparation method of high-purity acetal, in particular to a method for separating and purifying two acetals and raw material alcohol by pressure swing distillation.
Background
At present, the reports of the application of methoxy butane (CAS: 76050-97-0) and methoxy iso-butane (CAS: 76050-98-1) are increasing, and from the reports, it can be found that two kinds of condensed ether compounds can be used as perfumes, additives, gasoline and diesel additives and the like independently, and can also be used as solvents, reaction media, extractants and the like in the research of preparation processes such as drug synthesis, cosmetic production, special chemical manufacture and the like, so that the applications are wide, and partial physicochemical properties of the methoxy butane and the methoxy iso-butane are shown in figure 1.
The two compounds are isomers, the molecular formulas are both C6H14O2, the molecular weights are both 118.17, the standard boiling points are respectively 119.4 ℃ and 110.0 ℃, and the chemical structural formulas are shown in figures 2 and 3. The two compounds are colorless transparent liquid at normal temperature and have different fruit flavors.
As for the production method of two compounds of methoxy-butane and methoxy-isobutane, the literature reports are few, and in a small amount of foreign literatures, only concentrated sulfuric acid is used as a catalyst, methylal and n-butanol or isobutanol are used as raw materials, and a crude product of the compound can be synthesized under the conditions of high temperature and high pressure. In earlier application research, the cetane numbers (CN is more than or equal to 60) of two compounds of methoxy-butane and methoxy-isobutane are higher, and the two compounds belong to high-oxygen organic compounds and are used as diesel oil blending components, so that on one hand, the cetane number of the cracked diesel oil can be effectively improved, the average CN is more than or equal to 45, and the national standard is met; on the other hand, the oxygen content of the diesel oil can be improved, the condensation point is reduced, the diesel oil is more fully combusted in the internal combustion engine, and the diesel oil is suitable for the natural environment of high altitude or high cold areas. In the application research of the two compounds, the results show that the cetane numbers (CN is less than or equal to 20) of n-butyl alcohol and isobutanol are low, the viscosity is high (VS: 3.0-4.5 mPas; about 5-10 times of the viscosity of diesel oil), and the two compounds have certain water absorption, so that the cetane number of the diesel oil is not improved if the two compounds are mixed and blended, the kinematic viscosity of the diesel oil is easily increased, the two compounds have certain water solubility, and the quality and the combustion effect of the two compounds are reduced. In conclusion, it is very necessary to realize the high-efficiency separation between p-methoxy-methoxybutane and n-butanol and methoxy-methoxyisobutane and isobutanol. After the applicant researches the published documents and patents, the detailed separation and purification method is not reported, and therefore, the applicant has carried out related research.
The applicant finds that binary azeotropic states exist between the methoxy methoxybutane and the synthetic raw material n-butyl alcohol and between the methoxy methoxyisobutane and the synthetic raw material isobutanol, the azeotropic proportions of the binary azeotropic states under the standard atmospheric pressure are respectively about 51mol% and 53mol%, if a conventional rectification separation technology is adopted, efficient separation is difficult to achieve, two industrial products of the high-purity methoxy methoxybutane and the high-purity methoxy methoxyisobutane cannot be obtained, and if an extraction or extraction rectification technology is adopted, a third compound is introduced, so that the subsequent separation difficulty is increased. Therefore, the applicant has intensively studied and found a method which can realize efficient separation and purification of the two compounds.
Disclosure of Invention
The invention aims to eliminate binary azeotropic states between methoxy methoxybutane and n-butanol and methoxy methoxyisobutane and isobutanol, provide a production process for preparing high-purity methoxy methoxybutane and methoxy methoxyisobutane, and ensure that high-purity products with the purity of over 99.9 percent can be produced, so that new applications of the compounds can be further developed.
The technical solution of the invention is as follows: by utilizing the characteristic that the azeotropic ratio of methoxy methoxybutane to n-butanol and methoxy methoxyisobutane to isobutanol is different under different pressures, a rectification separation process of pressure swing rectification combined operation is introduced, clean and efficient separation is realized, an extraction separation method is abandoned, other compounds are not introduced, the separation process steps are increased, and the separation difficulty is reduced.
In order to achieve the purpose, the invention provides the following technical scheme: a method for separating and purifying two acetals and raw material alcohol by pressure swing distillation takes two crude products of methoxy methoxybutane and n-butyl alcohol and methoxy methoxyisobutane and isobutanol as separation materials, and the proportion of two compounds in the two crude products is respectively 1 percent to 99 percent to 1 percent;
the specific process comprises the following steps: introducing the two crude products into a reduced pressure rectifying tower, wherein the pressure value in the rectifying tower is 0.001-0.1 MPa, the theoretical plate number of the rectifying tower is 1-50, the reflux ratio is 1: 100-100: 1, collecting tower top fraction and tower bottom effluent, conveying the tower top fraction of the reduced pressure rectifying tower into a feed inlet in a pressurized rectifying tower, returning the tower bottom effluent of the reduced pressure rectifying tower into a synthesis reaction kettle for recycling, the pressure in the pressurized rectifying tower is 0.1-1.0 MPa, the theoretical plate number of the rectifying tower is 1-50, the reflux ratio is 1: 100-100: 1, respectively collecting the effluent to obtain tower top fraction and tower bottom, conveying the tower top fraction of the pressurized rectifying tower back into the feed inlet in the reduced pressure rectifying tower for mixing and recycling with the crude products, and separating the tower bottom effluent of the pressurized rectifying tower into high methoxy butane products and methoxy isobutane products with purity of over 99.9%.
Compared with the prior art, the invention has the beneficial effects that: the method for separating and purifying two acetals and raw material alcohol by pressure swing distillation introduces a rectification separation process of pressure swing distillation combined operation, utilizes the property that different azeotropic proportions exist between methoxyl butane and n-butyl alcohol and methoxyl isobutane and isobutanol under different pressures, realizes clean and efficient separation, skillfully designs the part which is not separated to form azeotropic composition materials for recycling separation again, and finally realizes the purpose of efficient separation.
Drawings
FIG. 1 is a graph of part of the physicochemical properties of methoxymethoxybutane and methoxymethoxyisobutane;
FIG. 2 is a molecular structural diagram of methoxymethoxybutane;
FIG. 3 is a molecular structural diagram of methoxymethoxy isobutane;
FIG. 4 is a flow chart of a pressure swing distillation separation process I;
FIG. 5 is a flow diagram of pressure swing distillation separation Process II;
Detailed Description
The present invention will be described in detail with reference to fig. 4 to 5 and the embodiments;
example 1
The pressure swing rectification method for separating methoxy methoxybutane and n-butanol is shown in figure 4. The rectification column T1 had 30 theoretical plates and a column diameter of 20 mm. Taking a mixture of methoxy methoxybutane and n-butanol with a mass ratio of 0.5:0.5 as a material to be separated, adding the material from a 16 th theoretical plate (with the number of plates from top to bottom), wherein the flow rate is 12mL/min, the rectification tower T1 is subjected to pressure reduction operation, the pressure is 5kPa, the reflux ratio at the top of the tower is 2:1, the temperature at the top of the tower is 43-44 ℃, and the temperature at the bottom of the tower is 50-51 ℃. Analyzing the overhead distillate by gas chromatography to obtain the mass ratio of the methoxy methoxybutane to the n-butyl alcohol of 0.91:0.09, conveying the overhead distillate to a middle storage tank for storage, conveying the overhead distillate to a rectifying tower T2 by a high-pressure pump, returning the overhead distillate to a synthesis section, and recycling the overhead distillate as the n-butyl alcohol raw material, wherein the mass ratio of the methoxy methoxybutane to the n-butyl alcohol in the material extracted from the tower bottom of the rectifying tower T1 is 0.001: 0.999.
The rectification column T2 had 20 theoretical plates and a column diameter of 13 mm. The high-pressure pump is used for conveying materials to be added from an 11 th theoretical plate (the number of tower plates is from top to bottom), the flow rate is 7mL/min, the rectifying tower T2 is in pressurization operation, the pressure is 0.15MPa, the reflux ratio of the tower top is 3:1, the temperature of the tower top is 130-130.5 ℃, and the temperature of the tower kettle is 138-139 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain that the mass ratio of the methoxy methoxybutane to the n-butanol is 0.5:0.5, conveying the distillate back to a feed inlet of a rectifying tower T1, and performing cyclic separation operation again; the mass ratio of the methoxy methoxybutane to the n-butanol in the distillate at the bottom of the rectifying tower T2 is 0.999:0.001, and the product is high-purity methoxy methoxybutane.
Example 2
The pressure swing distillation double tower and the pressure swing distillation separation flow are the same as the embodiment 1. Taking a mixture of methoxy methoxybutane and n-butanol with a mass ratio of 0.6:0.4 as a material to be separated, adding the material from a 16 th theoretical plate of a rectifying tower T1, wherein the flow rate is 12mL/min, the rectifying tower T1 is subjected to pressure reduction operation, the pressure is 10kPa, the reflux ratio at the top of the tower is 2:1, the temperature at the top of the tower is 53-54 ℃, and the temperature at the bottom of the tower is 61-62 ℃. Analyzing the overhead distillate by gas chromatography to obtain the mass ratio of the methoxy methoxybutane to the n-butyl alcohol of 0.87:0.13, conveying the overhead distillate to a middle storage tank for storage, conveying the overhead distillate to a rectifying tower T2 by a high-pressure pump, returning the overhead distillate to a synthesis section, and recycling the overhead distillate as the n-butyl alcohol raw material, wherein the mass ratio of the methoxy methoxybutane to the n-butyl alcohol in the material extracted from the tower bottom of the rectifying tower T1 is 0.001: 0.999.
The distillate at the top of the rectifying tower T1 is conveyed to the 11 th theoretical plate of the rectifying tower T2 by a high-pressure pump and is added, the flow rate is 8mL/min, the rectifying tower T2 is operated at normal pressure, the pressure is 0.1MPa, the reflux ratio at the top of the rectifying tower is 2.5:1, the temperature at the top of the rectifying tower is 113-113.5 ℃, and the temperature at the bottom of the rectifying tower is 122-123 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain that the mass ratio of the methoxy methoxybutane to the n-butanol is 0.6:0.4, conveying the distillate back to a feed inlet of a rectifying tower T1, and performing cyclic separation operation again; the mass ratio of the methoxy methoxybutane to the n-butanol in the distillate at the bottom of the rectifying tower T2 is 0.999:0.001, and the product is high-purity methoxy methoxybutane.
Example 3
The pressure swing rectification method for separating methoxy methoxybutane and n-butanol is shown in figure 5. The rectification column T3 had 20 theoretical plates and a column diameter of 20 mm. Taking a mixture of methoxy methoxybutane and n-butanol with a mass ratio of 0.3:0.7 as a material to be separated, adding the material from a 11 th theoretical plate (with the number of plates from top to bottom), wherein the flow rate is 14mL/min, the rectification tower T3 is subjected to pressure reduction operation, the pressure is 6kPa, the reflux ratio at the top of the tower is 3:1, the temperature at the top of the tower is 43-44 ℃, and the temperature at the bottom of the tower is 50-51 ℃. Analyzing the overhead distillate by gas chromatography to obtain the mass ratio of the methoxy methoxybutane to the n-butyl alcohol of 0.90:0.10, conveying the overhead distillate to a middle storage tank for storage, conveying the overhead distillate to a rectifying tower T4 by a high-pressure pump, returning the overhead distillate to a synthesis section, and recycling the overhead distillate as the n-butyl alcohol raw material, wherein the mass ratio of the methoxy methoxybutane to the n-butyl alcohol in the material extracted from the tower bottom of the rectifying tower T3 is 0.001: 0.999.
The rectification column T4 had 30 theoretical plates and a column diameter of 13 mm. The high-pressure pump is used for conveying materials to be added from a 16 th theoretical plate (the number of tower plates is from top to bottom), the flow rate is 6mL/min, the rectifying tower T4 is in pressurization operation, the pressure is 0.21MPa, the reflux ratio of the tower top is 2:1, the temperature of the tower top is 139-139.5 ℃, and the temperature of the tower bottom is 148-149 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain that the mass ratio of the methoxy methoxybutane to the n-butanol is 0.3:0.7, conveying the distillate back to a feed inlet of a rectifying tower T3, and performing cyclic separation operation again; the mass ratio of the methoxy methoxybutane to the n-butanol in the distillate at the bottom of the rectifying tower T4 is 0.999:0.001, and the product is high-purity methoxy methoxybutane.
Example 4
The pressure swing distillation double tower and the pressure swing distillation separation flow are the same as the embodiment 3. Taking a mixture of methoxy methoxybutane and n-butanol with a mass ratio of 0.6:0.4 as a material to be separated, adding the material from an 11 th theoretical plate of a rectifying tower T3, wherein the flow rate is 12mL/min, the rectifying tower T3 is subjected to pressure reduction operation, the pressure is 10kPa, the reflux ratio at the top of the tower is 2:1, the temperature at the top of the tower is 51-52 ℃, and the temperature at the bottom of the tower is 60-61 ℃. Analyzing the overhead distillate by gas chromatography to obtain the mass ratio of the methoxy methoxybutane to the n-butyl alcohol of 0.87:0.13, conveying the overhead distillate to a middle storage tank for storage, conveying the overhead distillate to a rectifying tower T4 by a high-pressure pump, returning the overhead distillate to the synthesis section, and recycling the overhead distillate as the n-butyl alcohol raw material, wherein the mass ratio of the methoxy methoxybutane to the n-butyl alcohol in the material extracted from the tower bottom is 0.001: 0.999.
The distillate at the top of the rectifying tower T3 is conveyed to the 16 th theoretical plate of the rectifying tower T4 by a high-pressure pump and is added, the flow rate is 8mL/min, the rectifying tower T4 is operated under normal pressure, the pressure is 0.1MPa, the reflux ratio at the top of the rectifying tower is 2.5:1, the temperature at the top of the rectifying tower is 105-105.5 ℃, and the temperature at the bottom of the rectifying tower is 114-115 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain that the mass ratio of the methoxy methoxybutane to the n-butanol is 0.6:0.4, conveying the distillate back to a feed inlet of a rectifying tower T3, and performing cyclic separation operation again; the mass ratio of the methoxy methoxybutane to the n-butanol in the distillate at the bottom of the tower is 0.999:0.001, and the product is a high-purity methoxy methoxybutane product.
Example 5
The pressure swing distillation process of separating methoxy iso-butane and iso-butanol is shown in figure 4. The rectification column T1 had 30 theoretical plates and a column diameter of 20 mm. The mixture of methoxy iso-butane and iso-butanol with the mass ratio of 0.5:0.5 is used as a material to be separated, the material is added from a 16 th theoretical plate (the number of plates is from top to bottom), the flow is 12mL/min, the rectification tower T1 is subjected to pressure reduction operation, the pressure is 8kPa, the reflux ratio of the top of the tower is 2:1, the temperature of the top of the tower is 42-42.5 ℃, and the temperature of the bottom of the tower is 49-50 ℃. And (3) analyzing the distillate at the tower top by gas chromatography to obtain methoxy isobutane and isobutanol with the mass ratio of 0.89:0.11, conveying the distillate at the tower top to an intermediate storage tank for storage, conveying the distillate at the tower top to a rectifying tower T2 by a high-pressure pump, returning the distillate at the tower bottom of the rectifying tower T1 to a synthesis section, and recycling the distillate as an isobutanol raw material.
The rectification column T2 had 20 theoretical plates and a column diameter of 13 mm. The high-pressure pump is used for conveying materials to be added from the 11 th theoretical plate (the number of tower plates is from top to bottom), the flow rate is 7mL/min, the rectifying tower T2 is in pressurization operation, the pressure is 0.16MPa, the reflux ratio at the top of the tower is 3:1, the temperature at the top of the tower is 119.5-120 ℃, and the temperature at the bottom of the tower is 129-130 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain methoxy iso-butane and iso-butanol with the mass ratio of 0.5:0.5, conveying the distillate back to the feed inlet of a rectifying tower T1, and performing cyclic separation operation again; the mass ratio of the methoxy isobutane to the isobutanol in the distillate at the bottom of the rectifying tower T2 is 0.999:0.001, and the product is high-purity methoxy iso-butane.
Example 6
The pressure swing distillation double tower and the pressure swing distillation separation flow are the same as the embodiment 5. The mixture of methoxy iso-butane and iso-butanol with the mass ratio of 0.6:0.4 is used as a material to be separated, the material is added from a 16 th theoretical plate of a rectifying tower T1, the flow rate is 12mL/min, the rectifying tower T1 is subjected to pressure reduction operation, the pressure is 12kPa, the reflux ratio of the top of the tower is 2:1, the temperature of the top of the tower is 52.5-53 ℃, and the temperature of a bottom of the tower is 60-61 ℃. And (3) analyzing the overhead distillate by gas chromatography to obtain methoxy isobutane to isobutanol with the mass ratio of 0.85:0.15, conveying the overhead distillate to an intermediate storage tank for storage, conveying the overhead distillate to a rectifying tower T2 by a high-pressure pump, returning the overhead distillate to a synthesis section, and recycling the overhead distillate as an isobutanol raw material, wherein the mass ratio of methoxy isobutane to isobutanol in the material extracted from the tower bottom of the rectifying tower T1 is 0.001: 0.999.
The distillate at the top of the rectifying tower T1 is conveyed to the 11 th theoretical plate of the rectifying tower T2 by a high-pressure pump and is added, the flow rate is 8mL/min, the rectifying tower T2 is operated under normal pressure, the pressure is 0.1MPa, the reflux ratio at the top of the rectifying tower is 2.5:1, the temperature at the top of the rectifying tower is 105-105.5 ℃, and the temperature at the bottom of the rectifying tower is 114-115 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain methoxy iso-butane and iso-butanol with the mass ratio of 0.6:0.4, conveying the distillate back to the feed inlet of a rectifying tower T1, and performing cyclic separation operation again; the mass ratio of the methoxy isobutane to the isobutanol in the distillate at the bottom of the rectifying tower T2 is 0.999:0.001, and the product is high-purity methoxy iso-butane.
Example 7
The pressure swing distillation process of separating methoxy iso-butane and iso-butanol is shown in figure 5. The rectification column T3 had 20 theoretical plates and a column diameter of 20 mm. The mixture of methoxy iso-butane and iso-butanol with the mass ratio of 0.32:0.68 is used as a material to be separated, the material is added from the 11 th theoretical plate (the number of trays is from top to bottom), the flow is 14mL/min, the rectification tower T3 is operated under reduced pressure, the pressure is 6kPa, the reflux ratio at the top of the tower is 3:1, the temperature at the top of the tower is 40-40.5 ℃, and the temperature at the bottom of the tower is 47-48 ℃. And (3) analyzing the distillate at the tower top by gas chromatography to obtain methoxy isobutane and isobutanol with the mass ratio of 0.89:0.11, conveying the distillate at the tower top to an intermediate storage tank for storage, conveying the distillate at the tower top to a rectifying tower T4 by a high-pressure pump, returning the distillate at the tower bottom of the rectifying tower T3 to a synthesis section, and recycling the distillate as an isobutanol raw material.
The rectification column T4 had 30 theoretical plates and a column diameter of 13 mm. The high-pressure pump is used for conveying materials to be added from a 16 th theoretical plate (the number of tower plates is from top to bottom), the flow rate is 6mL/min, the rectifying tower T4 is in pressurization operation, the pressure is 0.19MPa, the reflux ratio at the top of the tower is 2:1, the temperature at the top of the tower is 126-126.5 ℃, and the temperature at the bottom of the tower is 136-137 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain the mass ratio of methoxyl group iso-butane to isobutyl alcohol of 0.32:0.68, conveying the distillate back to the feed inlet of a rectifying tower T3, and performing cyclic separation operation again; the mass ratio of the methoxy isobutane to the isobutanol in the distillate at the bottom of the rectifying tower T4 is 0.999:0.001, and the product is high-purity methoxy iso-butane.
Example 8
The pressure swing distillation double tower and the pressure swing distillation separation flow are the same as the embodiment 7. The mixture of methoxy iso-butane and iso-butanol with the mass ratio of 0.7:0.3 is used as a material to be separated, the material is added from an 11 th theoretical plate of a rectifying tower T3, the flow rate is 12mL/min, the rectifying tower T3 is subjected to pressure reduction operation, the pressure is 6kPa, the reflux ratio at the top of the tower is 3:1, the temperature at the top of the tower is 40-40.5 ℃, and the temperature at the bottom of the tower is 47-48 ℃. And analyzing the overhead distillate by gas chromatography to obtain methoxy isobutane to isobutanol with the mass ratio of 0.89:0.11, conveying the overhead distillate to an intermediate storage tank for storage, conveying the overhead distillate to a rectifying tower T4 by a high-pressure pump, returning the overhead distillate to a synthesis section, and recycling the overhead distillate as an isobutanol raw material, wherein the mass ratio of methoxy isobutane to isobutanol in the material extracted by the tower bottom is 0.001: 0.999.
The distillate at the top of the rectifying tower T3 is conveyed to the 16 th theoretical plate of the rectifying tower T4 by a high-pressure pump and is added, the flow rate is 9mL/min, the rectifying tower T4 is operated under normal pressure, the pressure is 0.1MPa, the reflux ratio at the top of the rectifying tower is 0.6:1, the temperature at the top of the rectifying tower is 105.5-106 ℃, and the temperature at the bottom of the rectifying tower is 114-115 ℃. Analyzing the distillate at the tower top by gas chromatography to obtain methoxy iso-butane and iso-butanol with the mass ratio of 0.7:0.3, conveying the distillate back to the feed inlet of a rectifying tower T3, and performing cyclic separation operation again; the mass ratio of the methoxy isobutane to the isobutanol in the distillate of the tower bottom is 0.999:0.001, and the product is high-purity methoxy iso-butane.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation. The use of the phrase "comprising one of the elements does not exclude the presence of other like elements in the process, method, article, or apparatus that comprises the element.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (1)
1. A method for separating and purifying two acetals and a raw material alcohol by pressure swing rectification is characterized in that: two materials, namely methoxy methoxybutane and n-butyl alcohol as crude products and methoxy methoxyisobutane and isobutanol as crude products, are used as materials to be separated, and the proportion of a corresponding acetal compound to raw material alcohol in each material is respectively 1 percent to 99 percent to 1 percent;
the specific process comprises the following steps: independently introducing each material into a reduced pressure rectifying tower, wherein the pressure value in the rectifying tower is 0.001-0.1 MPa, the theoretical plate number of the rectifying tower is 1-50, the reflux ratio is 1: 100-100: 1, collecting tower top fraction and tower bottom effluent, conveying the tower top fraction of the reduced pressure rectifying tower into a feed inlet in a pressurized rectifying tower, returning the tower bottom effluent of the reduced pressure rectifying tower into a synthesis reaction kettle for recycling, returning the pressure in the pressurized rectifying tower to 0.1-1.0 MPa, collecting the theoretical plate number of the rectifying tower to 1-50, and the reflux ratio is 1: 100-100: 1, respectively collecting the effluent to obtain tower top fraction and tower bottom fraction, conveying the tower top fraction of the pressurized rectifying tower back into the feed inlet in the reduced pressure rectifying tower for mixing and recycling with the crude product, and separating the effluent in the kettle of the pressurized rectifying tower into methoxy methoxybutane product or methoxy methoxyisobutane product with purity of more than 99.9%.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104119202A (en) * | 2014-07-29 | 2014-10-29 | 河北工业大学 | Energy-saving technique for separating methanol-acetone azeotrope by variable-pressure rectification |
| CN104447240A (en) * | 2014-11-10 | 2015-03-25 | 中国海洋石油总公司 | Method for preparing high-purity methylal |
| CN104761430A (en) * | 2015-03-12 | 2015-07-08 | 赛鼎工程有限公司 | Process of varying-pressure thermal-coupling rectification separation of methylal from methanol |
-
2017
- 2017-10-27 CN CN201711021557.3A patent/CN108794310B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104119202A (en) * | 2014-07-29 | 2014-10-29 | 河北工业大学 | Energy-saving technique for separating methanol-acetone azeotrope by variable-pressure rectification |
| CN104447240A (en) * | 2014-11-10 | 2015-03-25 | 中国海洋石油总公司 | Method for preparing high-purity methylal |
| CN104761430A (en) * | 2015-03-12 | 2015-07-08 | 赛鼎工程有限公司 | Process of varying-pressure thermal-coupling rectification separation of methylal from methanol |
Non-Patent Citations (2)
| Title |
|---|
| Isobaric vapor–liquid equilibrium for the binary systems of 1-propanol + 1-(methoxymethoxy)-butane and 1-butanol + 1-(methoxymethoxy)-butane at 101.3kPa;Song Yuhe等;《Fluid Phase Equilibria》;20150225;第388卷;第18页 * |
| 聚甲氧基二甲醚生产的污染防治及清洁生产;陈勇民;《科技创新导报》;20150901(第25期);第90-92页 * |
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